I am upgrading a site and I wanted to add collective.collectionfilter to it.
For some reason, the portals disappear (or more precisely: some of it disappears) after selecting.
The add-on works if I add a new Plone site on the same Zope, and as far as I can tell: with the same add-ons.
Changing theme (to barcelona) and view of the collection does not help.
Any suggestion on how to troubleshoot this?